Bates et al. United States Published Patent Application U.S. 2004/0067000 discusses a minimally-invasive optical-acoustic device for vascular and non-vascular imaging. It discloses an elongated optical imaging guidewire, catheter, or like probe with one or more ultrasound transducers at its distal end to provide ultrasound energy to nearby tissue or the like. Light energy produced at the external instrumentation is transmitted to the distal end of the implanted instrument, where it is converted to sound energy that is directed at nearby tissue or the like. Sound energy returned by such tissue modulates light energy at the distal end of the implanted section of the instrument. Such modulated light is then communicated to back to the proximal end of the instrument, and then to externally located diagnostic instrumentation.